CVE-2019-17638

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Last Modified: UTC

Important Important Impact What does this mean?
7.7 CVSS v3 Base Score

Description

The MITRE CVE dictionary describes this issue as

In Eclipse Jetty, versions 9.4.27.v20200227 to 9.4.29.v20200521, in case of too large response headers, Jetty throws an exception to produce an HTTP 431 error. When this happens, the ByteBuffer containing the HTTP response headers is released back to the ByteBufferPool twice. Because of this double release, two threads can acquire the same ByteBuffer from the pool and while thread1 is about to use the ByteBuffer to write response1 data, thread2 fills the ByteBuffer with other data. Thread1 then proceeds to write the buffer that now contains different data. This results in client1, which issued request1 seeing data from another request or response which could contain sensitive data belonging to client2 (HTTP session ids, authentication credentials, etc.). If the Jetty version cannot be upgraded, the vulnerability can be significantly reduced by configuring a responseHeaderSize significantly larger than the requestHeaderSize (12KB responseHeaderSize and 8KB requestHeaderSize).

Additional Information

External References

Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2019-17638

Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2019-17638

Content from bugs.eclipse.org is not included.https://bugs.eclipse.org/bugs/show_bug.cgi?id=564984

Content from www.jenkins.io is not included.https://www.jenkins.io/security/advisory/2020-08-17/

Affected Packages and Issued Red Hat Security Errata

Products / Services Components State Errata
Red Hat Enterprise Linux 6 jetty-eclipse Not affected
Red Hat Enterprise Linux 7 jetty Not affected
Red Hat Fuse 7.8.0 jetty Fixed RHSA-2020:5568
Red Hat JBoss Fuse 6 jetty Not affected
Red Hat JBoss Fuse Service Works 6 jetty Not affected
Red Hat OpenShift Container Platform 3.11 jenkins Fixed RHSA-2020:4223
Red Hat OpenShift Container Platform 4.3 jenkins Fixed RHSA-2020:3808
Red Hat OpenShift Container Platform 4.4 openshift4/ose-jenkins Fixed RHSA-2020:4220
Red Hat OpenShift Container Platform 4.5 jenkins Fixed RHSA-2020:3841
Red Hat Single Sign-On 7 jetty Not affected
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).

CVSS v3 Score Breakdown Red Hat NVD
CVSS v3 Base Score 7.7 9.4
Attack Vector Network Network
Attack Complexity High Low
Privileges Required None None
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact High High
Integrity Impact High High
Availability Impact Low Low

CVSS v3 Vector

Red Hat CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L

NVD CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

Red Hat CVSS v3 Score Explanation

Attack Complexity Low (AC:L) -> Attack Complexity High (AC:H):

We disagree with the original scoring of a low attack complexity, we believe the impact is significantly different depending on the specific applications handling, that is to say a successful attack depends on conditions beyond the attacker's control, we believe those conditions are -

*) The attack has a prerequisite of a response header injection, in other words the attacker would need to be able to alter the response header contents to achieve the double free.

*) In order to have a high impact upon confidentiality and integrity there is significant conditional factors to do with timing that must be present

  • The attacker and target client must have active connections at the same time

  • The same ByteBuffer space must be acquired by two different threads at the same time, this is a race condition and would require repeated and sustained attack

  • The Bytebuffer must be of the correct sizing to avoid corruption to achieve C:H I:H

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

 For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

What can I do if my product is listed as "Will not fix"?

 A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.

What can I do if my product is listed as "Fix deferred"?

 A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

 A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

I have a Red Hat product but it is not in the above list, is it affected?

 The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

 In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our This content is not included.Red Hat Vulnerability Scanner Certification program.